FRIDAY, May 22, 2020 (HealthDay News) -- In Northern California, the incidence of hospitalization for acute myocardial infarction decreased during the COVID-19 pandemic period, according to a letter to the editor published online May 19 in the New England Journal of Medicine.
Matthew D. Solomon, M.D., Ph.D., from the Kaiser Permanente Oakland Medical Center in California, and colleagues examined weekly incidence rates of hospitalizations for acute myocardial infarction (ST-segment elevation myocardial infarction [STEMI] or non-ST-segment elevation myocardial infarction [NSTEMI]) before and after the first reported COVID-19 death in Northern California on March 4, 2020. Incidence rates (events per 100,000 person-weeks) for the COVID-19 period (March 4 to April 14, 2020) were compared to those of the pre-COVID-19 period (Jan. 1 through March 3, 2020).
The researchers observed a decrease of up to 48 percent in the weekly rates of hospitalization for acute myocardial infarction during the COVID-19 period. A total of 1,051 hospitalization events occurred during Jan. 1 to March 3, 2020 (incidence rate, 4.1 per 100,000 person-weeks), while 61 hospitalization events occurred from April 8 through April 14, 2020 (incidence rate, 2.1 per 100,000 person-weeks; incidence rate ratio, 0.52; 95 percent confidence interval [CI], 0.40 to 0.68; P < 0.001). Similar decreases were seen among patients with NSTEMI and STEMI (incidence rate ratios, 0.51 [95 percent CI, 0.38 to 0.68] and 0.60 [95 percent CI, 0.33 to 1.08], respectively).
"In a large diverse community setting in California, the incidence of hospitalization for acute myocardial infarction declined after March 4, 2020, during the COVID-19 pandemic, more than would be expected on the basis of typical seasonal variation alone," the authors write. "Similar findings have been noted in northern Italy."